Diaphragm type pump



March 11, 1958 A. c. SAXE 2,826,154

DIAPHRAGM TYPE PUMP Filed pct. 28, 1955 2 She'ets-Shet'l IN VEN TOR.

0. Sue.

March 11, 1958" c. s xE 2,826,154

DIAPHRAGM TYPE PUMP 2 Sheets-Sheet 2 Filed Oct. 28, 1955 INVENTOR.file-mun (134x:

United States Patent DIAPHRAGM TYPE PUMP Arthur C. Saxe, Columbus, Ohio,assignor to The Jaeger glfiiichine Company, Columbus, Ohio, acorporation of Application October 28, 1955, Serial No. 543,534

1 Claim. (Cl. 103-150) My invention relates to a diaphragm type pump. Ithas to do, more particularly, with a heavy duty diaphragm pump of thetype used in construction work, etc.

With a pump of this type when handling water which containssediment-forming materials, there is a tendency for the material todeposit on the bottom of the pressure chamber. For example, if the pumpis handling water which carries sand and clay along with cement, whichmay drain away from concrete forms in the bottom of an excavation, thereis a tendency to form a deposit which will build up in successive layerson the bottom of the pressure chamber. This deposit will eventuallybuild up to such an extent that such excessive pressure will be exertedon the downward stroke of the pump that breakage of the drivingmechanism, frame or housing of the pump might occur. The same type ofbreakage might occur when a solid object enters between the diaphragmand the bottom of the pressure chamber. It has been proposed to overcomethis disadvantage by providing a yieldable connection in the connectingrod of the pump driving mechanism but although the rod yields to preventbreakage, the offending deposit or object will still be present in thechamber and must be removed manually before resuming operation of thepump.

It is the main object of my invention to provide a simple inexpensivestructure in a diaphragm pump of the type indicated which will preventdamage to pump parts when excessive resistance to downward movement ofthe diaphragm is encountered due to a deposit or solid object on thebottom of the pressure chamber and which will further act to break upthe deposit or displace the object to facilitate removal by passage onthrough the outlet of the pump.

In the accompanying drawings I have illustrated a preferred embodimentof my invention. In these drawings:

Figure 1 is a plan view of a diaphragm pump in which my invention isembodied.

Figure 2 is a side elevational view of the pump showing my inventionapplied thereto.

Figure 3 is a detail in plan of the pressure chamber of the pump.

Figure 4 is a vertical sectional view taken on line 4-4 of Figure 3.

Figure 5 is an enlarged view in vertical section showing how myinvention will break up a deposit on the bottom of the pressure chamber.

With reference to the drawings, in Figures 1 and 2 I have illustrated adiaphragm pump of the type to which my invention may be applied. Thispump consists of the usual power unit which reciprocates a connectingrod 11 that is connected to a diaphragm 12. The diaphragm 12 forms theupper flexible wall of a pressure chamber 13 in the usual way. The pumpshown is in such a position that the axis of the pressure chamber isvertical which is its normal operating position. The connection of thelower end of the rod 11 to the diaphragm 12 includes a dependingserrated skirt 14 which will move downwardly into the pressure chamberupon downward flexing of the diaphragm 12.

Instead of the pressure chamber 13 being provided with the usual rigidbottom, it is provided with a yieldable wall in the form of a seconddiaphragm 15 which is suitably clamped to the lower edge of the chamber13 by means of an annular fitting 16. This fitting is provided with aspider structure which supports a central inverted cup 17. Passingupwardly through this cup is an adjusting bolt 18 which extends upwardlythrough metal discs 19 clamped to the central part of the diaphragm 15.The inner end of the bolt 18 is threaded into a nut 20. Between thelower disc 19 and the upper end of the cup 17, I provide a compressionspring 21. This spring is adapted to be preloaded to a desired extent byproper adjustment of the bolt 18 relative to the nut 20.

In the operation of my structure, assuming that the pump is pumpingwater in which there is material that tends to form a deposit D on thebottom of the chamber 13 as shown in Figure 5, due to the fact that thespring 21 is preloaded, the initial formation of the deposit will haveno eiiect on operation of the pump, since the spring is designed toresist normal pumping pressure. However, if the deposit D builds up tosuch an extent that excessive pressure is created in the chamber 13 uponthe downward movement of the diaphragm 12, the diaphragm 15 at thebottom of the chamber will yield. This yielding, as indicated in Figure5, will break up the deposit and the particles of the deposit will passon out through the outlet of the pump. The yielding of the bottom willpermit the continued downward movement of the pump diaphragm 12 so thatthe skirt 14 may eventually contact the deposit of material and aid inbreaking it up. A similar action will occur if a solid object entersbetween the skirt 14 and the flexible bottom diaphragm 15, the flexingof the bottom aiding in displacing the object so that it will pass onthrough the pump. The annular fitting 16 will be preferably attached tothe lower edge of the pressure chamber by suitable removable bolts 22which will permit removal of the fitting and the associated diaphragm 15along with the bolt and spring structure 18 and 21 which the fitting 16carries. The inner end of the bolt 18 may be battered or otherwiseformed to prevent displacement of the nut 20. Since the bottom walldiaphragm 15 is clamped at its peripheral edge and since the clampingdiscs 19 are provided at the central area of this diaphragm, thereremains a flexible annular unsupported area which will flutter as aresult of the pressure and suction strokes of the pumping diaphragm 12so as to tend to prevent the formation of a deposit on the bottom walldiaphragm.

It will be apparent from the above description that the flexible oryieldable wall structure need not be the bottom of the pressure chamberbut is preferably the wall directly opposite the main diaphragm of thepump. The yieldable wall structure prevents damage to the pump whenexcessive pressures occur on the pressure stroke of the pump diaphragmand aids in eliminating the material creating the excessive pressure.

Various other objects will be apparent.

Having thus described my invention what I claim is:

A heavy duty diaphragm pump for pumping water or other liquids whichcontain sediment-forming materials or solid objects comprising asubstantially vertically disposed pump chamber, a flexible pumpingdiaphragm forming the upper wall of said chamber, mechanical meansconnected to said diaphragm for positively flexing it to produce apumping action, a flexible diaphragm forming the bottom wall of saidchamber having a central connecting area, a peripheral clamping edge andan annular area therebetween, means for clamping said diaphragm at itsperipheral edge to the bottom of said pump chamber, and means connectedto said connecting area of said bottom wall diaphragm to prevent bodilyyielding downwardly of said diaphragm until a predetermined pressure isdeveloped in said chamber on the pressure stroke of said pumpingdiaphragm due to the formation of a heavy deposit on said bottom Walldiaphragm or the positioning of a solid object thereon and forpreventing bodily yielding upwardly on the suction stroke of saidpumping diaphragm, said last-named means comprising connecting meansengaging the central area of said bottom Wall diaphragm leaving theunsupported flexible an nular area which will flutter as a result of thepressure and suction strokes of the pumping diaphragm so as toReferences Cited in the file of this patent UNITED STATES PATENTS1,938,403 Rockwell Dec. 5, 1933 2,434,802 Jacobs Ian. 20, 1948 2,466,618Stocks Apr. 5, 1949 2,619,907 Paterson Dec. 2, 1952

